Combined telegraph, signal, and telephone system.



I w. A. PBOEGKMAN. QOMBINED TELEBBQPH, SIGNAL, AND TELEPHONE SYSTEM.

APPLIOATN! main-mus,1910

1,004,767. I WW. 3,1911.

UNI ED; ermine rArENT'oEEIoE.

' WILLIAM A, EEoEckMAN, or ST. LOUIS, MISSOURI, assIeNoE or ONE-HALF T0 y PETER. r. FINNEG-AN, or sea LOUIS, MISSOURI.

Tcall whom it may conccrnb Be it known that I, WILLIAM A. FROECK- MA N', & citizen of the United States, residing tems, of which the following is a full, clear,

and exact description, such as will enable others skilled in the art to which 1t appertains to make and use the same.

This invention relates to combined tele graph, signal and telephone systems such as are used by city fire departments for estabofiice or headquarters of the department and the various engine-houses oresub-stations at which the fire engine companies are stationed. The system that is generally used in most city fire departments for establishing communication between the central office and the engine-houses comprises a plurality of telephone circuits, telegraph circuits, commonly termed joker circuits, and bell circuits or ..sub-joker circuits, the enginehouses or substations. in a certain district being connected to one of each of said different circuits. The telephone circuits are of "course used forcarrying on conversationsbetween the headquarters and the engine houses, and the telegraph circuits and "the bellcircuits are used for'sending out alarms from the central officefeach engine-house 5 beingequipped with atelephone, a telegraph instrument, and a bell-or other suitable sig-" nal, which telegraph instrument and bell arej connected in series with the telegraph circuit and the bell circuit, respectively, of the-district in which the engine-house is located. Inview of the fact that the engine-houses are connected in series with the central office "or exchange, it is often diflicult 'to locate a break in the system, and during the time a circuit is open all of the instruments on that particular circuit are out of service.

Qne'ob ect of my invention is to provide a combined telegraph, signal and telephone system which is so designed that a break in 'any circuit of the system can be located quickly.

Another object isto provide a system of the character described which is so designed that a break in one of the circuits thereof Specification of Letters Patent. Application filed May 5, 1910. Serial No. 559,562.

' office or exchange.

COMBINED TELEGRAPH, SIGNAL, AND TELEPHONE SYSTEM.

has no effect on the instruments which are connected tosaid circuit between the central exchange and the point where the break occurs. Y

Another object is to provide a system of the character described which comprises automatic means for notifying all of the sub-stations beyond a break in the telegraph circuit that their telegraph instruments are out of service. And still another object is to provide. a system of the character described that comprises a sufficient number of metallic conductors between the central station and the sub-stations to enable'temporary communication to be established *etween the central ofiice and sub-stations under practically all conditions by cr0ss-connect1ng an instrument at the sub-station that is on a dead line with a live line through which'current is passing. Other objects and desirable features of my invention will be hereinafter pointed out.

' Thefigure of the drawing is a diagram- 15 matic view of a system constructed in accordance with my invention.

Referring to said drawing,'the reference character A designates the central oflice or headquarters of a city fire alarm department,

and B and C designate two of the engine- 'liouses or sub-stations of the department which" receive instructions from theicenti'al strument, as herein shown, or merely a sounder, a bell or audible si nal 2, a grounded striking key 3, and a telephone 4, all of said instruments being of any preferred type or"design. The central office A is provided with atelephone switch-board 5, a key 6 for operating the telegraph instruments 1 and the bells 2 in the various en ine+houses, and also a grounded signal be operated by the striking keys 3 at the various engine-houses of the department.

Instead of connecting the telegraph inn struments and signals at the engine house in series with the, central exchange A, as has. 100

heretofore been thegenera-l practice, I connect said devices in multiple with metallic conductors that lead from the central exchange.

Patented 0a.. 3, 1911,-

Each of the engine houses is provided with a telegraph instru- 8&5" ment 1 which may either be a recording in- 7 which is adapted to break is between houses B and C for any break beyond B has no effect on the instruments at said house. Itds very seldom that both sides of a line will be broken at the same time but in case this unusual condition exists the telegraph instrument can be cross-connected or tapped onto either: side of the bell circuit 9 or the telephone circuit 10 in any suitable manner, as, for example, by means of the plug cords 30 and 31v at the sub stations and central exchange which cooperate with the lug sockets 85, 9F and 10 that are arranged? in the telegraph circuit, the bell circuit and the telephone circuit, respectively.

1 While :thebell I,circuit is primarily used for operating thdsignals 2 at the enginehouses and also for forming one side of the connecting circuit between the striking keys 3 and the signal 7, this bell circuit can also be used for telephoning in case a break occure in the telephone circuit 10 by plugging into the bell circuit and actuating the'magneto-generator 23 which sends out a; pulsating current over the. bell circuit 9. and through the condenser 24 to the magnetobell 25 which is grounded, it being,'.-.; of course, understood that each engine-house is equipped with a magneto-bell and condenser and suitable telephone acks for establishing cross-connections between the various circuits. f

As previously stated, one of the principal advantages of a system of the character which I have described is that it is a very simple-matter to locate a breakin any of the circuits owing to the fact that the multiple connection between the circuits and inj struments causes all of the instruments be- 40 located beyond the breakare rendered in operative is also a ,verydesirable feature,

yond the break tobecome inoperative and prevents the break from aflecting the instruments arranged on the other side of same, namely, the instruments locatedbetween the break and the source of electrical supply. The fact that only the instruments that are and still another exceedingly desirable feature of any improved system is that there are a sufficient number of metallic conductors between the central exchange and the various sub-stations to enable a metallic connection to beestablished between said sub-stations andcent-ral stations under practically all conditions. The means for automatically notifying the sub-stations whenever a break occurs in the telegraph circuitis a desirable feature but it is not absolutely essential to the successful operation of my system. It is immaterial what particular kind or type of instruments or apparatus the sub-stations and central exchange are provided with for invention, broadly stated, consists in a combined I telegraph, signal and telephone system comprising substations equipped are. used for energizing the various circuits,

with telegraph instruments, signals and telephones that are connected in multiple with the circuits which energize them.

While I have herein stated that batteries it will, of course, be obvious that generators .or any suitable means for producing electrical currents could be substituted for the batteries. 1

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is: y

1. A'fire alarm system, comprising a telegraph circuit, a signal circuit and a telephone circuit, corresponding instruments at the sub-stations or engine-houses connected in multiple with their respective circuits, and means at the engine-houses for establishing cross connections between said cir,c 'i'.iits so as to utilize one side of a circuit worm a returnLa-round a break in a different circuit.

2. A fire alarm'system, comprising separate and distinct metallic circuits for telegraphing, telephoning and signaling, appropriate instruments at the engine-houses or sub-stations of the system which are connected in multiple with their respective circuits, a common battery at the central exchange for energizing the telegraph circuit and the "slgnaling circuit, and means for utillzlng one side of either of said circuits to form a return around a break in a different circuit. 7

In a fire alarm system, a metallic,cir-

cuit which leads from a central exchan e to sub-stations or engine-houses, telegrap instruments at the sub-stations connected in multiple with said circuit, signal circuits at said sub-stations provided with signals, relays arranged in said metallic circuit for controlling said signal circuits, and means I under control of the operator at the central exchange for sending out current of a cer- I tainvoltage to operate said signals without operating said telegraph instruments and also a current of a different voltage to operate said telegraph instruments.

4. In-a system of the character described, a telegraph circuit leading from a central exchange to a sub-station, a telegraph instrument, and a signal at said sub-station connected in multiple with said circuit, and means under control of the operator at the central exchange for sending out current-of a certain voltage to operate said signal without operating said instrument and also a current of a different voltage to operate said instrument.

5. A fire alarm system comprising a central exchange, a plurality of sub-stations or engine-houses, said central exchange and substations or engine-houses being .each provided' with a telegraph instrument, a signal- I ing instrument and a telephone instrument, a pluralityof separate and distinct metallic electrical circuits connecting the central excentral exchange and sub-stations which are 5 change instruments with the, sub-station inadapted to be.operated by said circuits, an strun'lents by multiple connection, and means independent means for energizing said tele-' for utiliaing any one of said circuits for opgraph circuit, an independent means for encrating any one of said instruments. ergizing said bell circuit, and means for uti- 6, A system of the character described, lizing either of said circuits for operating 20 comprising a telegraph circuit and a bell cirany of said instruments. cuit leading from a central exchange to sub- In testimony whereof I hereunto aflix my stations, telegraph instruments and bells at signature in the presence of two Witnesses, said substations connected in multiple with this second day of May 1910. said telegraph circuit and bell circuit, rel lVILLIAM A. FROECKMAN. spectively, a common source of electrical vvVitnesses: energy at the central exchange for supply- WnLLs L. CHURCH, ing current to said circuits, signals at the l Gnomes BAKEWELL. 

